Understanding Hemoptysis and Its Causes

Hemoptysis, the expectoration of blood from the lower respiratory tract, can vary from blood-streaked sputum to frank blood, with causes ranging from infectious, pulmonary, neoplastic, vasculitic, vascular, traumatic, coagulopathic to miscellaneous. Infections like bacterial or viral pneumonias, neoplastic conditions such as lung cancers, and diffuse alveolar hemorrhage from systemic diseases are significant contributors to hemoptysis. Vascular causes like pulmonary emboli or arteriovenous malformations, traumas, or coagulation disorders can also lead to this condition.